Fiber board



' To all whom it may concernf' j Patented Dec. 22, 1925.

1,566,310 PATENT? OFFICE.

ALBERT L. CLAZPI, OF DANVERS, MASSACHUSETTS, ASSIGNOIR TO BECKWITH MANU- FACTURING COMPANY, OF BOSTON, MASSACHUSETTS, A CORPORATION OF MASSA- CHUSETTS.

7 F0 Drawing.

Be it known that I, ALBERT L. Curr, a citizen of the United States, residing at Danvers, in the county of Essex and State of Massachusetts, have invented new and useful Improvements in Fiber Board, of which the following is a specification.

This invention relates to the manufacture of hard, dense, fiber board or like products. a I have discovered that, it cellulose fibers are beaten fora suflicient period of time to ensure the hydration thereof and are then formed by suitable paper-making machinery into a sheet of the desired thickness, it is possible by heat and pressure to convert the sheet or portions thereof into a relatively hard, dense, and more or less horny product.

For example, if sulphate pulp or waste kraft paper with sufficient water to insure circulation be beaten hard in a beating engine for 20 to 24: hours, the fibers arehighly hydrated, and the stock is slow or slimy due to the mucilaginous hydrate thereby produced while the felting property of the fibers is not destroyed. Such stockmay then be formed into asheet of the desired thickness by a wet machine so-called, removed from the make-up roll and dried. Button blanks may then be died out or stamped from the sheet, and, when such blanks are .then subjected in a suitable mold-tea pres v sure of about 2500; pounds .per square inch while heated to a temperature of 160 to 220 F., the buttons thereby. produced are hard, dense and horny-,due to. the cementing -or binding action of the hydrated fibers. With less beneficial results, the stock may be beaten for 8 to 10 hours, whereas, when boa-ten for less than 5 or 6 hours, the fibers of' the sheet thereafter produced have no binding or cementing action when subjected to heat and pressure. Apparently the gelatinous or mucilaginous hydrate produced by the long beating of the cellulose stock. even when the uncombined water is removed during the drying of the sheet, is effective, when the material is subjected to heat and high pressure, in cementing the mass together.

For increasing the water-resistant qualities of the molded or compressed product, I may add to the stock a quantity of sodium resinate, say 5% to 10% by" weight of the dry cellulose stock and, when the heating 0 eration has been carried on to the desire ex-' tent, aluminum resinate may be precipitated 1 and. high pressure in suitable molds. But- .beating cellulosic material until the fibers FIBER BOARD.

Application filed August 23, 1921. Serial lie. 494,638.

may be. used for electric insulation and for other uses to which hard fiber has heretofore been. employed.

For use as printing plates, the compressed board may be coated o'r-not as'desired. Under heat and high pressure it receives and retains the impressions of a matrix. The cellulose-mucilage under heat and pressure cements and binds the fibrous mass into a homogeneous horn-like, dense, hard article, 7

whether the latter be a sheet, a plate, a phonograph record, a button or other element. J

If it be desired to impart a luster or fine finish to the finished product, as in the case of buttons for example, the blanks may be coated with a solution of gums, resins, or

phenol resins, and, after the solvent has" evaporated, the blanks are subjected to heat tonsthus formed have a fine appearance and polish or luster.

What I claim is r 1. The herein described method. of making dense hard fiber board, which comprises beating cellulosic material until the fibers are well hydrated, then sheeting the stock .on a paper-making machine and drying the same, and subjecting thesheet or portions thereof to heat and high pressureof an order of about 2500 pounds to the square inch. 2. The herein described method of making dense hard fiber board, which comprlses.

are well hydrated, then sheeting the stock on. a paper making machine and drying the same, cutting'blanks from such sheet, coating such blanks with a resinous solut1on,

hi h' pressure. s

n-testimony whereof I have aflixed my signature.

g I ALBERT L. OLAPP.

and'flmolding such blanks under heat and 

